875917 - Use xor instead of movl to zero a register in a few places

Status: RESOLVED FIXED

(Core :: JavaScript Engine, enhancement)

Description

[Dan Gohman [:sunfish]]

CodeGenerator-x86-shared.cpp and CodeGenerator-x86.cpp both currently use mov to zero a register in a context where the condition codes aren't live.

Comment 1

[Dan Gohman [:sunfish]]

Attachment: a proposed fix

Comment 2

[Luke Wagner [:luke]]

Comment on attachment 753934 [details] [diff] [review]
a proposed fix

Thanks!

Comment 3

[Dan Gohman [:sunfish]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/44385c2f40be

Comment 4

[Sean Stangl [:sstangl]]

just as a stupid follow-up nit, note that if the else branch has brackets, then our style requires all branches to have brackets.

Comment 5

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/44385c2f40be

Comment 6

[Dan Gohman [:sunfish]]

Attachment: fix missing braces

Comment 7

[Dan Gohman [:sunfish]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/5c085ef24d2c

Comment 8

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/5c085ef24d2c